Earth’s Energy Budget Remained Out of Balance Despite Unusually Low Solar Activity

Adam Voiland, NASA’s Earth Science News Team, in a repost.  The research brief by Hansen et al is here.

A new NASA study underscores the fact that greenhouse gases generated by human activity — not changes in solar activity — are the primary force driving global warming.

The study offers an updated calculation of the Earth’s energy imbalance, the difference between the amount of solar energy absorbed by Earth’s surface and the amount returned to space as heat. The researchers’ calculations show that, despite unusually low solar activity between 2005 and 2010, the planet continued to absorb more energy than it returned to space.

A graph of the sun’s total solar irradiance shows that in recent years irradiance dipped to the lowest levels recorded during the satellite era. The resulting reduction in the amount of solar energy available to affect Earth’s climate was about .25 Watts per square meter, less than half of Earth’s total energy imbalance. (Credit: NASA/James Hansen)

Total solar irradiance, the amount of energy produced by the sun that reaches the top of each square meter of the Earth’s atmosphere, typically declines by about a tenth of a percent during cyclical lulls in solar activity caused by shifts in the sun’s magnetic field. Usually solar minimums occur about every eleven years and last a year or so, but the most recent minimum persisted more than two years longer than normal, making it the longest minimum recorded during the satellite era.

Pinpointing the magnitude of Earth’s energy imbalance is fundamental to climate science because it offers a direct measure of the state of the climate. Energy imbalance calculations also serve as the foundation for projections of future climate change. If the imbalance is positive and more energy enters the system than exits, Earth grows warmer. If the imbalance is negative, the planet grows cooler.

James Hansen, director of NASA’s Goddard Institute for Space Studies (GISS) in New York City, led the research. Atmospheric Chemistry and Physics published the study last December.

Hansen’s team concluded that Earth has absorbed more than half a Watt more solar energy per square meter than it let off throughout the six year study period. The calculated value of the imbalance (0.58 Watts of excess energy per square meter) is more than twice as much as the reduction in the amount of solar energy supplied to the planet between maximum and minimum solar activity (0.25 Watts per square meter).

“The fact that we still see a positive imbalance despite the prolonged solar minimum isn’t a surprise given what we’ve learned about the climate system, but it’s worth noting because this provides unequivocal evidence that the sun is not the dominant driver of global warming,” Hansen said.

According to calculations conducted by Hansen and his colleagues, the 0.58 Watts per square meter imbalance implies that carbon dioxide levels need to be reduced to about 350 parts per million to restore the energy budget to equilibrium. The most recent measurements show that carbon dioxide levels are currently 392 parts per million and scientists expect that concentration to continue to rise in the future.

Football’s heartland will become dangerously hot

Back in November, GE’s TXCHNOLOGIST blog pointed out that climate change “could ruin Texas football,” indeed all southern U.S. football:

The effects of climate change, so far, have been most noticeable in Texas, where a terrible drought has dried up football fields in small towns that used to look forward to Friday nights above all. But climate change will have a terrible effect on communities throughout the cradle of football in the Southern and plains states.

Florida, Alabama, Louisiana, Texas. The home states of the last five college football champions? Yes. But these are also states that are projected to experience 150-180 days a year with peak temperatures over 90 degrees Fahrenheit by the final decades of the 21st Century. That’s almost six months of the year. In parts of Florida and Texas the number is likely to exceed 180 days a year. Not only will the high temperatures be hotter, the lows will also be higher, so there will be less relief from the sultry conditions. This warming effect will have devastating effects on the ecology and economies of these area and make watching and playing football outdoors almost unbearable.

This isn’t news to Climate Progress readers (see NASA’s Hansen: “If We Stay on With Business as Usual, the Southern U.S. Will Become Almost Uninhabitable.”  But it is going to come as a big shock to the football fans throughout the region, many of whom have been heavily disinformed by their politicians and favorite media outlets.

Indeed, it is the conservative southern U.S., especially the South central and South east, who have led the way in blocking serious climate action, as it were, making yesterday’s worst-case scenario into today’s likely outcome (see “Our hellish future: Definitive NOAA-led report on U.S. climate impacts warns of scorching 9 to 11°F warming over most of inland U.S. by 2090 — and that isn’t the worst case, it’s business as usual! — the source of the figure above).

I’m a football fan, born and raised in New York State, and I will be rooting today for Manning to beat Brady — once again.  Ironically, it looks like warming is going to make football more of a northern U.S. game — though that will be among the least consequential of the myriad impacts our greed and myopia is thrusting on our children and grandchildren and billions around the world

GE’s blog points out a key danger of the ever-worsening heat and heat waves:  “Players will run increasing risk of hyperthermia.“  Andrew Grundstein, of the Climatology Research Laboratory at the University of Georgia, has analyzed heat-related deaths of football players since 1980.  In August, he explained his findings in a UCS press call and pointed out some of his remarkable findings, including the fact that “the conventional wisdom that coaches can reduce the risk by practicing in the morning is inaccurate“:

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The Super Bowl is pure American Red, White and Blue. And organizers are trying to throw in a shade of green as well.

This year, the National Football league is undertaking a variety of initiatives — from an urban forestry program to donation of a small solar array — to “green” its operations. The most highly publicized initiative is the purchase of renewable energy credits (RECs) to offset all energy use during the game and the month-long set up.

Kara Scharwath of Triple Pundit had a piece on the NFL’s plan to be “super green.”

To help reduce the impact of that energy consumption, the National Football League and the Indianapolis Super Bowl XLVI Host Committee are partnering with Green Mountain Energy to purchase 15,000 megawatt hours of renewable energy certificates (RECs) generated at wind farms in North Dakota to offset the power associated with the event.

It’s encouraging to see a prominent organization like the NFL making an effort to clean up its operations. But the devil is in the details.

At a second glance, one has to wonder if this REC purchase really makes an impact at all.

RECs are not physical electricity, but the market value of the “environmental attribute” of that clean electricity. As readers of Climate Progress may know, we often write about our skepticism of RECs. (See: Clean Energy Trainwreck: Why Most RECs are Bad, and How to Find the Good Ones.)

By purchasing RECs, organizations like the NFL can claim that they are “powered” by renewable energy, when in fact they are not. Here’s the problem: The RECs bought for the Super Bowl are from existing projects in North Dakota. They are not helping build new projects, and are therefore providing a marginal incentive that does very little to expand the industry.

In an email exchange with Auden Schendler, vice president of sustainability at the Aspen Skiing Company (and periodic Climate Progress blogger), he expressed his underwhelming response to the announcement:

“Okay, so the farm is up, and the RECs are therefore not doing anything at all. And in my past work I’ve shown that the marginal income from these credits have virtually no influence on new wind farms. What would have influence? Getting congress to re-approve the tax incentives for wind. That would require an ad during the Super Bowl, not buying RECs.

There are a heck of a lot of things the NFL could be doing to actually try to move the needle in the public consciousness, argues Schendler:

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Pile of leaves, or power plant?

It’s chore day. You’ve raked the leaves, taken out the recycling, and emptied out the old junk in your garage. But wait — don’t toss it all out! You have all the ingredients for your very own homemade solar system.

If new advances in “biophotovoltaics” research are any indication, you may someday be able to create your own solar “goo” from plant matter and apply it to metal or glass.

A group of researchers has found a way to break down plant matter, isolate photosynthetic molecules, and then spread those molecules on a metal or glass substrate. So theoretically, you could take a bag full of leaves and grass, pour in a mixture of chemicals to break them down, and then finish your chores by painting the liquid on your windows to produce electricity. Not bad for a day’s work.

Researchers have been working on biophotovoltaics for many years, only to be hindered by low efficiencies, rapid degradation, and difficulties in spreading the photovoltaic “goo” onto a substrate. But nine scientists have just published research on new advances that boost performance and may allow for inexpensive substrates like recycled glass and metal to be used:

To improve photovoltaic performance we increased the light absorption cross-section without changing the footprint by departing from the traditional flat electrode geometry in favor of mesoscopic, high-surface area semiconducting electrodes (TiO₂ nanocrystals and ZnO nanowires). Finally, we showed how high affinity peptide motifs¹⁰ bioengineered to promote selective adsorption to specific substrates can enhance photovoltaic performance. These materials, geometries and design resulted in simple, robust biophotovoltaic devices of unprecedented performance.

In short, the researchers have created a method to stabilize the photosynthetic molecules. And by coating a substrate with titanium dioxide and zinc oxide nanowires, they can now turn any sort of glass or metal material into a working solar cell with efficiencies better than ever before.

It’s a fascinating discovery. But don’t get too excited yet. Efficiencies are still extraordinarily low — only at .01%. They’d need to be about 10 times that in order to power a light or charge a cell phone. So for the foreseeable future, don’t expect to be painting your house with a bag of grass clippings.

However, as research advances and performance continues to improve, MIT physicist Andreas Mershin says it could be perfect for remote applications in developing countries. In the video below, Mershin explains the significance of the findings: